Dave Mustaine -- the lead singer of Megadeth -- believes Barack Obama "staged" the massacre in Aurora, CO in a sick, twisted plot to pass a gun ban.
Mustaine made the comments on stage at an August 7 performance in Singapore ... when he told the crowd, "Back in my country, my president ... he's trying to pass a gun ban, so he's staging all of these murders, like the 'Fast And Furious' thing down at the border ... Aurora, Colorado, all the people that were killed there ... and now the beautiful people at the Sikh temple."
(Scroll to 2:35 in the video)
He continued, "I don't know where I'm gonna live if America keeps going the way it's going because it looks like it's turning into Nazi America."
